Sex-based heterogeneity in outcomes following frontline EVT strategies for anterior circulation stroke

Background Endovascular thrombectomy (EVT) is the standard treatment for large vessel occlusion stroke, with stent retriever (SR) and contact aspiration (CA) as the predominant frontline techniques. Although sex-related differences in EVT outcomes are increasingly recognized, whether the comparative effectiveness of SR versus CA differs by sex remains unclear. This study evaluated sex-related heterogeneity in outcomes between frontline SR and CA using the Taiwan Registry of Endovascular Thrombectomy for Acute Ischemic Stroke (TREAT-AIS). Methods TREAT-AIS is a multicenter prospective EVT registry. Patients with anterior circulation stroke who received frontline SR or CA alone were included; those treated with combined techniques were excluded. We assessed the EVT technique-by-sex interaction in the overall cohort and performed sex-stratified propensity score matching (PSM) to evaluate 3-month functional and safety outcomes. Results Of 1,752 patients, a significant technique-by-sex interaction was observed for independent functional outcome (modified Rankin Scale 0–2; P for interaction = 0.016): CA was associated with this outcome among female (adjusted odds ratio [aOR], 3.39; 95% CI, 1.40–10.18) but not male patients (aOR, 0.87; 95% CI, 0.50–1.56). After 1:4 PSM, independent functional outcome was more frequent with CA than with SR among female (26.0% vs. 8.6%; aOR, 3.94; 95% CI, 1.11–14.02) but not male patients (35.1% vs. 38.1%; aOR, 0.73; 95% CI, 0.35–1.53). A similar nonsignificant trend was observed for ambulatory functional outcome in female patients, whereas symptomatic intracranial hemorrhage and mortality were comparable in both sexes. Conclusions This registry suggests potential sex-related heterogeneity in outcomes across frontline EVT strategies; these hypothesis-generating findings warrant validation in larger cohorts.